1. Field of the Invention
The present invention relates to charging cables for electric vehicles. More particularly, the present invention relates to a charging cable, used for charging the electric vehicle, and a method of controlling the charging cable that allows an electric storage device used for driving a vehicle to be charged from an external power supply.
2. Description of the Related Art
Generally, electric vehicles are provided with an electrical storage device (for example, secondary battery or capacitor), and travels by using driving force generated by the electric power stored in the electric storage device. The electric vehicle includes, for example, an electric vehicle, a hybrid vehicle, and a fuel-cell electric vehicle.
Recently, a technique is proposed that the electric storage device that is provided in these electric vehicles is charged by a commercial power source that delivers high power generation efficiency. This technique is expected to improve, fuel consumption efficiency of the hybrid vehicle, for example. In particular, attention is focused on the technique that the electric storage device provided in the electric vehicle is charged by the commercial power source (relatively low voltage power source of 100V and 200V for example) that is supplied for home use.
Japanese Patent Application Publication No. 7-29639 (JP-A-7-29639) describes an electric vehicle charging connector that improves connection workability.
In addition, SAE Electric Vehicle Conductive Charge Coupler, published in the United States in November 2001 by SAE International, describes the standards related to vehicle inlets and connectors in a charging system of electric vehicles, and recommends that a common charging cable and connector be used among different automobiles.
As described above, when charging cables and connectors for electric vehicles are standardized, a common cable can commonly be used for several vehicles, and also the same cable can continuously be used for a newly purchased vehicle.
Unfortunately, when the charging cable is frequently used for a long time, the charging cable including its connector may deteriorate due to the use over the service life limit. If a deteriorated cable is used, the cable itself and vehicle side devices such as an electric storage device can be damaged.